Rail tie plate placing vehicle and method

Abstract

A railroad tie plate placing vehicle uses a crawler track to place plates upon rail ties. The crawler track is meshed to a magnetic wheel which holds tie plates to the crawler track until the tie plates have actually contacted a tie. The crawler track at least partially propels the vehicle down the railroad track when the vehicle is placing plates. A tie detector switch is used to control gates which gate tie plates onto the conveyor and magnetic wheel upon detection of a tie such that a tie plate released by the gates will reach a release point in the closed loop of the conveyor at the same time as the release point reaches the tie whose detection triggered the gating of the tie plate.

What is claimed is: 
     
       1. A rail tie plate placing vehicle comprising: (a) a main frame;   (b) a moving conveyor extending in a closed loop, said conveyor supported by said main frame and operable in a plate placing mode to place tie plates upon ties of a railroad track as the vehicle moves down the railroad track;   (c) a first gate for gating the conveyance of tie plates by said conveyor, said first gate disposable in a blocking state wherein it blocks the conveyance of a leading tie plate and disposable in an open state wherein it allows passage of a leading tie plate for conveyance by movement of said conveyor;   (d) holding means for holding tie plates against said conveyor and allowing the release of tie plates at a common predetermined release point on said closed loop for immediate disposal upon a tie; and   (e) a tie detector supported by said main frame for detection of ties at a detection point forward of said release point; and wherein said tie detector causes said first gate to open for passage of a tie plate corresponding to the detection of a tie such that the tie plate which was allowed passage by said first gate arrives at said release point when said vehicle has moved said release point over the detected tie.     
     
     
       2. The rail tie plate placing vehicle of claim 1 wherein said conveyor is operable to propel said vehicle along a track. 
     
     
       3. The rail tie plate placing vehicle of claim 2 wherein said conveyor applies at least a portion of the weight of the vehicle to the ties by way of the tie plates. 
     
     
       4. The rail tie plate placing vehicle of claim 3 wherein said conveyor is a crawler track. 
     
     
       5. The rail tie plate placing vehicle of claim 1 wherein said conveyor is a flexible conveyor having a plate conveying surface with an upwardly facing portion, a downwardly facing portion, and a transitional portion between said upwardly facing portion and said downwardly facing portion, and further comprising holding means cooperating with said conveyor for holding tie plates against said transitional portion and said downwardly facing portions of said plate conveying surface and for releasing tie plates at said release point, said release point being disposed at said downwardly facing portion. 
     
     
       6. The rail tie plate placing vehicle of claim 5 further comprising a magnetic wheel rotating upon movement of said conveyor, and wherein said holding means comprises a plurality of permanent magnets mounted to said magnetic wheel. 
     
     
       7. The rail tie plate placing vehicle of claim 6 wherein said conveyor is a crawler track disposed to crawl on a railroad track. 
     
     
       8. The rail tie plate placing vehicle of claim 6 wherein said tie detector is a switch mounted for actuation by ties. 
     
     
       9. The rail tie plate placing vehicle of claim 1 wherein the tie plate path distance from said first gate to said release point is equal to the distance from said detection point to said release point, and said tie detector causes said first gate to assume its open state immediately upon detection of a tie. 
     
     
       10. The rail tie plate placing vehicle of claim 1 further comprising a plate detector for detection of a tie plate at a place on said conveyor downstream of said first gate, and wherein said plate detector is operable to cause said first gate to assume its blocking state prior to complete passage of a leading tie plate past the first gate such that the leading tie plate moves with said conveyor, but any following tie plates are blocked. 
     
     
       11. The rail tie plate placing vehicle of claim 1 wherein said first gate is mounted adjacent a first side of said conveyor, and further comprising a second gate mounted adjacent a second side of said conveyor and operable in like fashion with said first gate for simultaneously gating tie plates by joint action of said first and second gates. 
     
     
       12. A rail tie plate placing vehicle comprising: (a) a main frame;   (b) a moving, closed loop, flexible conveyor supported by said main frame and operable in a plate placing mode to place tie plates upon ties of a railroad track, and wherein said conveyor includes a plate conveying surface having an upwardly facing portion, a downwardly facing portion and a transitional portion between said upwardly facing portion and said downwardly facing portion; and   (c) holding means cooperating with said conveyor for holding tie plates against said transitional and downwardly facing portions of said plate conveying surface and for releasing tie plates at a release point from said downwardly facing portion for placement upon ties, and wherein said conveyor is disposed such that it contacts a tie plate at the same time as the tie plate contacts a tie.   
     
     
       13. The rail tie plate placing vehicle of claim 12 wherein said conveyor applies at least a portion of the weight of the vehicle to the ties by way of the tie plates. 
     
     
       14. The rail tie plate placing vehicle of claim 13 wherein said conveyor is a crawler track. 
     
     
       15. The rail tie plate placing vehicle of claim 14 further comprising a magnetic wheel rotating upon movement of said conveyor, and wherein said holding means comprises a plurality of permanent magnets mounted to said magnetic wheel. 
     
     
       16. The rail plate placing vehicle of claim 12 wherein said conveyor is a crawler track disposed to crawl on a railroad track. 
     
     
       17. The rail tie plate placing vehicle of claim 16 further comprising a first gate for gating the conveyance of tie plates by said conveyor, said first gate disposable in a blocking state wherein it blocks the conveyance of a leading tie plate and disposable in an open state wherein it allows passage of a leading tie plate for conveyance by movement of said conveyor, and a tie detector supported by said main frame for detection of ties at a detection point forward of said release point; and wherein said tie detector causes said first gate to open for passage of a tie plate corresponding to the detection of a tie, and wherein said conveyor is operable such that the tie plate which was allowed passage by said first gate arrives at said release point when said vehicle has moved said release point over the detected tie. 
     
     
       18. The rail tie plate placing vehicle of claim 17 wherein said tie detector is a switch mounted for actuation by ties. 
     
     
       19. The rail tie plate placing vehicle of claim 17 further comprising a plate detector for detection of a tie plate at a place on said conveyor downstream of said first gate, and wherein said plate detector is operable to cause said first gate to assume its blocking state prior to complete passage of a leading tie plate past the first gate such that the leading tie plate moves with said conveyor, but any following tie plates are blocked. 
     
     
       20. The rail tie plate placing vehicle of claim 17 wherein said first gate is mounted adjacent a first side of said conveyor, and further comprising a second gate mounted adjacent a second side of said conveyor and operable in like fashion with said first gate for simultaneously gating tie plates by joint action of said first and second gates. 
     
     
       21. The rail tie plate placing vehicle of claim 17 further comprising an inclined conveying means having a plate placement surface adapted to receive tie plates thereon for movement to a lower end of said conveying means, and wherein said lower end terminates above said conveyor such that tie plates placed on said conveying means are deposited upon said conveyor. 
     
     
       22. The rail tie plate placing vehicle of claim 12 further comprising a magnetic wheel rotating upon movement of said conveyor, and wherein said holding means comprises a plurality of permanent magnets mounted to said magnetic wheel. 
     
     
       23. A method of placing rail tie plates upon ties from a tie plate placing vehicle, the steps comprising: (a) moving the vehicle along a railroad track;   (b) detecting ties on the railroad track;   (c) automatically gating a tie plate by way of a first gate for movement with a closed loop, moving conveyor for each detected tie, each gating of a tie plate resulting from a corresponding detection of a tie;   (d) moving each gated tie plate to a release point of said conveyor such that the gated tie plate is at the release point when the vehicle has moved sufficiently that the release point is immediately over the detected tie whose detection caused the gating of that gated tie plate; and   (e) releasing each gated tie plate from further movement with the vehicle when it arrives at said release point.   
     
     
       24. The method of claim 23 wherein each tie plate is gated for movement with the conveyor upon the detection of a tie. 
     
     
       25. The method of claim 23 wherein said conveyor is moving at the same speed as said vehicle. 
     
     
       26. The method of claim 25 further comprising the step of propelling the vehicle by movement of said conveyor and wherein the vehicle is moving during said releasing step. 
     
     
       27. The method of claim 26 wherein the conveyor is a crawler track which contacts the railroad track and said releasing step results at least partially from the weight of the vehicle causing tie plates to stop moving with the vehicle such that each tie plate is deposited on a tie. 
     
     
       28. The method of claim 27 further comprising the steps of detecting plates at a place on said conveyor downstream of said first gate and causing the first gate to assume a blocking state upon detection of a plate. 
     
     
       29. The method of claim 23 further comprising the step of holding tie plates to the conveyor by permanent magnets in a magnetic wheel which rotates upon movement of said conveyor. 
     
     
       30. The method of claim 23 wherein said releasing step occures upon a tie plate contacting a tie, while the tie plate is still in contact with the conveyor.